The present invention may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present invention relates to devices for performing a biopsy. More specifically, the invention relates to devices used to retrieve biopsy tissue samples and to cauterize the resulting wound.
As shown in
The forceps 100 according to the exemplary embodiment of the present invention comprises a pair of hinged jaws 106, 108 including overlapping teeth 112, or other similar cutting surfaces. The opposing cutting surfaces of the jaws 106, 108 may be brought together over the sample tissue once the distal head 102 has been advanced to the sampling site within, for example, a body lumen or cavity. The exemplary jaws 106, 108 pivot about a hinge 110, so that they can open and close using a remote actuator 104, that may be operated by a user from outside the patient's body.
The jaws 106, 108 are preferably shaped to form a sample holder, such as a sample cup 114 that becomes an enclosed sample chamber 116 once the jaws 106, 108 are closed. The sample chamber 116 retains the sample for removal from the body while protecting the sample from contamination during removal. The jaws 106, 108 are preferably designed to automatically enclose the sample within the chamber 116 after the sample has been excised to prevent loss of the sample during retrieval. Those of skill in the art will understand that different shapes and locations of the sample chamber 116 may be used, without departing the scope of the present invention.
Multiple surfaces of the biopsy forceps 100 are coated with an insulating material to prevent the non target tissue and the sample tissue from being damaged. For example, the insulation may comprise PTFE or PFA materials, ceramics or any other coating that reduces heat transfer and is electrically non-conductive. The insulating coating may be sprayed, dipped or painted on the device. As shown in the drawings, the device according to this embodiment comprises coated, non-conductive surfaces 120 formed as described above as well as non-coated, conductive surfaces 122 which deliver energy to cauterize the sampling site. A large portion of the exemplary device is coated with the non-conductive insulation, including the shaft 104 and the sample cup 114. As would be understood by those skilled in the art, for forceps according to alternate embodiments using other forms of energy (e.g., laser) to cauterize tissue, the insulation need not be electrically non-conductive and may be simply thermally insulative. For example, an electrically conductive, thermally insulative material such as conductive acetal polymer black carbon filled Pomaflux CN-F may be used to the shaft 104 and/or the sample cup 114. A laser may be used to heat the jaws 106, 108 for cauterizing tissue when need to be thermally insulated but not electrically insulated.
When the jaws 106, 108 are closed, the conductive portions 122 form a generally bullet shaped cauterization tool that may be used to stop bleeding within the sampling site. The user may, for example, visualize the site via an endoscope to direct the distal head 102 to the site of bleeding to cauterize and seal the wound. Because of the insulation disposed on the surfaces 120, the portion of tissue cauterized may be accurately targeted minimizing inadvertent cauterization of the surrounding tissue. The sample within the sample chamber 116 is also protected from damage during the cauterization steps by insulation coated on the inside portions of the jaws 106, 108.
A second embodiment of a biopsy forceps according to the present invention is shown in
In this embodiment, the conductive surfaces 222 of the device are limited to the distal tip of the jaws 206, 208. For example, the outer distal ends of the forceps 202 are left uncoated to form a substantially circular cauterization zone. According to this embodiment, the shape of the conductive surfaces 222 directs RF energy toward a grounding pad and away from the sample of tissue contained within the sample chamber 216. In other exemplary embodiments, the conductive surfaces 222 may be located on external surfaces of sidewalls of the jaws 206, 208, e.g., about 180° apart. For example, the conductive surfaces 222 may be located on opposite sides of the jaws 206, 208 adjacent the contacting edges and/or on upper external portion of the jaw 206 and a lower external portion of the jaw 208 when the contacting edges are in a horizontal plane. In this manner, the forceps 202 need only be rotated, at most, about 90° to align one of the conductive surfaces 222 with the target tissue region to be cauterized. In another exemplary embodiment, the conducting surfaces 222 may be selectively activated, e.g., one on/one off. Preferably, the conductive surfaces 222 are semi-circular, forming a substantially circular shape when the jaws 206, 208 are closed.
The preceding embodiments of the biopsy forceps may be based on existing forceps used for sample tissue retrieval. For example, the Barracuda and the Tiger Shark lines of biopsy forceps, and the Stone Retrieval Devices Basket line manufactured by the Boston Scientific Corporation of Natick, Mass., may be modified to operate in accord with the teachings of the present invention by applying non-conductive coatings in to selected areas as described above.
In alternate embodiments of the present invention, the jaws or cutting elements of the device are not used to perform the cauterization of the sampling area. Instead, a separate media is used to cauterize the wound, for example by directing RF or other energy to the target tissue. According to these embodiments, a path of least resistance is provided toward the tissue to be cauterized (e.g., toward a grounding pad located on an opposite side of the tissue to be cauterized) and away from the sample tissue held within the device. The cauterization media may be a fixed or a movable protrusion that extends from the biopsy forceps towards the target tissue.
As shown in
A biopsy forceps 320 as shown in
Furthermore as would be understood by those skilled in the art, other mechanisms and/or forms of energy may be used to cauterize the tissue. For example, a resistance type heater may be utilized instead of the laser and RF energy systems described above. Alternatively, a dual lumen may be provided in the shaft of the biopsy forceps according to the invention through which a wire loop (e.g., of nickel-chrome wire) for RF or other forms of electric energy may be advanced to the sampling site to cauterize the tissue. As would be understood, such devices may be powered by an external battery, RF generator or other power source and, as in the embodiments described above, the loops may be fixed or may be telescoping from the shaft of the device.
As shown in
In another embodiment, the basket 410 is formed of a plurality of filaments 404 with one or more of the filaments 404 transmitting energy to the target tissue. For example, the one or more filaments 404 may be formed of an electrically conductive wire or fiber-optic cable to transmit RF, laser or other energy to a cauterization element disposed at the distal tip 406. For example, where one of the filaments 404 is used as a hot element for cauterization, the location of this filament 404 with respect to the interior of the basket 410 is selected to minimize the affect of the heat on a tissue sample retained within the basket 410. In addition, selected portions of the filament 404 may be insulated (thermally and/or electrically) to maximize energy transfer to the target tissue while minimizing energy transfer to sample tissue retained within the basket 410.
The present invention has been described with reference to specific exemplary embodiments. Those skilled in the art will understand that changes may be made in details, particularly in matters of shape, size, material and arrangement of parts. Accordingly, various modifications and changes may be made to the embodiments. The specifications and drawings are, therefore, to be regarded in an illustrative rather than a restrictive sense.
This application claims the priority to the U.S. Provisional Application Ser. No. 60/843,963, entitled “TISSUE SAMPLE PROTECTING CAUTERIZING BIOPSY FORCEPS,” filed Sep. 12, 2006. The specification of the above-identified application is incorporated herewith by reference.
Number | Date | Country | |
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60843963 | Sep 2006 | US |